Klarna Docs - Before you start
Before you start

Ready to offer Klarna Express Checkout to your customers? Here's what you need to know before integrating the product with your store's website.

Are you using an e-commerce platform or a Payment Service Provider (PSP)? Check if they support our Express checkout:

Klarna offers two types of checkout experiences: a one-step checkout and a multistep checkout:

  • One-step checkout is the fastest of express checkout journeys. If your goal is to create the fastest checkout that requires none to minimal efforts from customers, then this is the optimal option to enhance your checkout. 
  • Multistep checkout is the personalized express journey. If you’re looking to offer your customers a seamless checkout experience, but still want to allow them the flexibility to pick between multiple shipping options, insert promo codes, or participate in upsell opportunities, this is the best choice for your checkout.

Use the feature matrix below to ensure you’re setting up the right express journey for your customers.

Feature One-step checkout Multistep checkout
Shipping optionsPlanned support in Q2 2024. Suitable for pre-selected or default shipping options before the customer enters the Express checkout flow. Suitable for complex shipping options like Next-Day delivery, Express delivery, or Click and collect.
Discount codes Discount codes can be applied on the cart page before the customer enters the Express checkout flow.Discount codes can be applied on the checkout page after the customer enters the Express checkout flow.
UpsellNot supported.Allows upselling after the customer enters the Express checkout flow.

For the biggest impact on conversion, choose the best placement for the Express checkout button. Refer to our button placement guidelines to optimize your customer journey for a faster checkout.

Before you integrate Express checkout, check that you meet the following prerequisites:

  1. Make sure to have a payment solution with Klarna. Before integrating Express checkout into your website, you need to have a merchant account with Klarna and Klarna payments or Klarna checkout integrated in your checkout.  
  2. Make sure to allowlist the domain of the page on which Express checkout will be integrated. If not all the domains are added to the allowlist, Express checkout will still load, however, the customer will see a "We couldn't load the next screen" error.
    To allowlist the domain URLs, follow these steps: 
  • Log into Klarna Merchant portal. If you want to test Express checkout, log into the playground Merchant portal. If you want to build a live integration, log into the production Merchant portal.
  • Once logged in, go to Payment settings > Client Identifiers. In the Allowed Origins for your integrations section, click Manage origins.   
  • In the Register new origin field, add your domain’s URL. Then, click Register. The registered domain is now listed in Allowed origins.

3. Generate a client identifier that will let you authenticate requests sent to Klarna:

  • Log into Klarna Merchant portal.
  • Once logged in, go to Payment settings > Client Identifiers.
  • To generate a new client identifier, navigate to Client Identifiers for your integrations and click Generate client identifier

If you’ve previously generated a client identifier for your store, you can use it to build your Express checkout integration.

Express button will be deprecated by the end of 2024. Make sure to migrate to Express checkout by then.

If you need support with Express checkout, please contact Klarna's merchant support